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MPC603e & EC603e RISC Microprocessors User's Manual
MOTOROLA
– Processor version register (PVR). This register is a read-only register that
identifies the version (model) and revision level of the PowerPC processor.
Implementation Note
—The processor version number is 6 for the PID6-
603e and 7 for the PID7v-603e. The processor revision level starts at 0x0100
and changes for each chip revision. The revision level is updated on all silicon
revisions.
—
Memory management registers
– Block-address translation (BAT) registers. The 603e includes eight block-
address translation registers (BATs), consisting of four pairs of instruction
BATs (IBAT0U–IBAT3U and IBAT0L–IBAT3L) and four pairs of data BATs
(DBAT0U–DBAT3U and DBAT0L–DBAT3L). See Figure 2-1 for a list of the
SPR numbers for the BAT registers.
– SDR1. The SDR1 register specifies the page table base address used in virtual-
to-physical address translation. (Note that physical address is referred to as
real address in the architecture specification.)
– Segment registers (SR). The PowerPC OEA defines sixteen 32-bit segment
registers (SR0–SR15). Note that SRs are implemented on 32-bit
implementations only. The fields in the segment register are interpreted
differently depending on the value of bit 0.
—
Exception handling registers
– Data address register (DAR). After a data access or an alignment exception,
the DAR is set to the effective address generated by the faulting instruction.
– SPRG0–SPRG3. The SPRG0–SPRG3 registers are provided for operating
system use.
– DSISR. The DSISR defines the cause of data access and alignment
exceptions.
– Machine status save/restore register 0 (SRR0). The SRR0 is used to save
machine status on exceptions and to restore machine status when an
rfi
instruction is executed.
– Machine status save/restore register 1 (SRR1). The SRR1 is used to save
machine status on exceptions and to restore machine status when an
rfi
instruction is executed.
Implementation Note
—The 603e implements the Key bit (bit 12) in the
SRR1 register in order to simplify the table search software. For more
information refer to Chapter 5, “Memory Management.”
— Miscellaneous registers
– The time base facility (TB) for writing. The TB is a 64-bit register pair that
can be used to provide time of day or interval timing. It consists of two 32-bit
registers—time base upper (TBU) and time base lower (TBL). The TB is
incremented once every four clock cycles.